Absorption compared with other forms, sleep, stress, migraine, cramps, elemental magnesium dose and precautions: what the studies really allow us to say about magnesium bisglycinate.
9 min read487
Potassium is vital, but supplements carry risks. Our guide covers needs, food sources vs. pills, and why medical advice is crucial before taking them.
By Claire Mercier8 min read450
Copper is essential in very small amounts. Supplementation is worth discussing only in specific situations; Wilson's disease, the liver, high-dose zinc, and stacking supplements all change the decision.
By Claire Mercier10 min read422
Magnesium citrate, bisglycinate, and oxide aren't interchangeable. Choose based on elemental magnesium content, your goal, and digestive tolerance.
By Claire Mercier9 min read393
Dietary folate, folic acid, and methylfolate: EFSA benchmarks, planning a pregnancy, the MTHFR mutation and genetic tests, food fortification, the 1,000 µg limit, the link with B12, and drug interactions.
By Claire Mercier8 min read369
Melatonin mainly acts as a rhythm signal. It can help with certain jet lag or falling-asleep difficulties, but timing, dose, and interactions matter a great deal.
By Claire Mercier8 min read369
Who should get their B12 tested, how to read the result, why absorption matters as much as diet, and when a supplement is no longer enough.
By Claire Mercier9 min read344
Retinol, beta-carotene, liver, multivitamins, pregnancy: vitamin A calls for a careful reading of the label. The risk mainly comes from stacking preformed vitamin A.
10 min read340
Iron bisglycinate may be better tolerated in some trials, particularly during pregnancy. The real question remains the diagnosis: a documented deficiency, an identified cause, the elemental iron dose, and interactions.
By Claire Mercier11 min read334
Vitamin B6 hides in B-complex products, magnesium, multivitamins, and "energy" formulas. The risk isn't dietary B6, but the prolonged stacking of supplements.
By Claire Mercier10 min read321
Psyllium forms a gel when mixed with water and can help relieve some types of constipation. Taking enough fluid, increasing the dose gradually and checking medication timing are essential.
By Claire Mercier10 min read313
Skin, joints, dietary collagen and hydrolyzed peptides: what human trials show, their limitations, and the precautions to know.
By Claire Mercier8 min read305
Zinc is essential, but a supplement doesn't automatically boost immunity. Needs, sources, what the Cochrane review shows on colds, the upper limit, copper, and interactions.
By Claire Mercier8 min read297
Selenium needs, Brazil nuts, supplements, the European safety limit of 255 µg, and results from the SELECT trial: benchmarks for avoiding overdose.
By Claire Mercier8 min read289
Iodine is essential for thyroid hormone production, but supplements are not for everyone. Diet, pregnancy, thyroid health and the risk of excess all matter.
By Claire Mercier8 min read287
A probiotic depends on its strain, its dose and the use it was studied for. What trials show for antibiotic-associated diarrhea and irritable bowel syndrome, and who should be cautious.
By Claire Mercier8 min read286
Vitamin K2 is said to "direct calcium toward the bones." What the trials actually show on bone density and fractures, what remains hypothetical for the arteries, and why the interaction with anticoagulants matters.
By Claire Mercier8 min read283
25(OH)D testing, intake benchmarks, sun exposure, D2 versus D3, the real effect on fractures, and the 100 µg limit: understanding vitamin D without supplementing blindly.
By Claire Mercier9 min read283
EPA, DHA, fish oil or algae oil: how to read an omega-3 supplement label, what trials show about the heart, and precautions to know.
By Claire Mercier8 min read281
Vitamin C needs, the best sources, what the Cochrane review shows about colds, why high doses are of little use, and the precautions to know.
By Claire Mercier8 min read280
Calcium supplements can fill a dietary gap, but more is not always better. Learn how to compare citrate and carbonate, read elemental calcium doses, and avoid excess intake and medication interactions.
By Claire Mercier16 min read279
Coenzyme Q10, ubiquinone, ubiquinol, heart failure, migraine, statins, male fertility, and Parkinson's disease: what the evidence actually allows us to say, indication by indication.
By Claire Mercier8 min read277
Vitamin E: food sources, what the major trials show on heart disease and cancer, a mortality signal at high doses, IU conversion, and bleeding risk.
By Claire Mercier8 min read273
Biotin, hair, deficiency and lab tests: why beauty megadoses promise more than the evidence supports.
By Claire Mercier8 min read260
Hot flashes, sleep, bones, mood: how to read the evidence on soy, vitamin D, calcium, magnesium, and herbs during perimenopause.
By Anja Vogel10 min read260